Glass Surface Shape Determination via Reflected Optical Imaging

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for determining the surface shape of curved glass sheets and analyzing optical distortion are inadequate for precision and objective assessment, leading to potential physical and optical defects in formed glass, which can cause issues during processing and installation in vehicle assembly plants.

Innovation Solution

A non-contact, opto-electronic method using a selectively oriented rigid surface with a pattern, such as a grid of alternating colored squares or spatially separated geometric shapes, to reflect light onto a glass sheet, capturing the altered image with an opto-electronic device for analysis, allowing for precise determination of surface shape and distortion measurement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional optical measurement methods are used to determine glass surface shape, then the measurement process is simple, but the measurement precision and ability to detect optical distortion is insufficient

Engineering Contradiction:
Improvesurface shape measurement precisionVSAvoidmeasurement system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

A planar target with a known pattern is introduced as an intermediary object. The target is positioned at a known location and orientation relative to the glass sheet, serving as a reference medium that enables precise measurement of surface shape and optical distortion through reflected light patterns.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The known pattern on the planar target is reflected by the glass sheet surface, creating a distorted copy of the original pattern. By analyzing the deviations between the expected and actual reflected patterns, the system precisely determines surface shape and optical distortion characteristics.

Inventive Principle:
Principle #26Copying

2Reliability

If automated optical systems are implemented to detect physical and optical defects, then defect detection capability is improved, but the system complexity and cost increase

Engineering Contradiction:
Improvedefect detection reliabilityVSAvoidautomated system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The measurement system serves multiple functions: it determines surface shape, quantifies optical distortion, and detects both physical and optical defects in the glass sheet. This multi-functionality is achieved through a single integrated optical setup using reflected light patterns, avoiding the need for separate specialized systems for each measurement type.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The system provides objective quantitative feedback about glass sheet quality by comparing the actual reflected light pattern against the expected pattern from the known target. This feedback mechanism enables automated detection and classification of defects, improving reliability while maintaining manageable system complexity through algorithmic analysis.

Inventive Principle:
Principle #23Feedback

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This method enables accurate, automated assessment of glass surface shape and optical distortion, reducing the occurrence of physical and optical defects in glass sheets, thereby improving the glass shaping production process and ensuring higher quality glass products.

Implementation Method 1

determining the surface shape of a curved, formed sheet of glass... by reflected optical imaging

Methodology Applied
Scientific EffectReflection: Reflection

Data Source

PatentEP2252856B1Method of determination of glass surface shape and optical distortion by reflected optical imaging
Publication Date: 2017.11.01 PILKINGTON GRP LTD
  • EP2252856B1 patent drawingFigure 1
  • EP2252856B1 patent drawingFigure 2
  • EP2252856B1 patent drawingFigure 3

AI summary

A non-contact, opto-electronic method to determine glass surface shape involves pattern projection in reflection from a screen. The pattern is formed of black and white or coloured squares with a central reference pattern taken as origin of the x-y axes in the subsequent quantitative analysis of the optical distortion in formed glass sheets or panels.